In a conventional casting reel for lure fishing in which a casting bundle is provided on the base portion of the fishing rod and a bait-casting reel is mounted, a thumb-retaining member for operating a clutch which can rotate freely is provided so as to extend transversely between reel side plates behind the spool. In operation, the thumb-retaining member is pushed so that it rotates downwards by the thumb of the hand holding the handle to disengage the clutch mechanism, while the tip of the thumb thumbs the flange surface of the spool. Examples of such a casting reel are disclosed in, for example, the specifications of U.S. Pat. Nos. 4,168,812 and 4,142,694, as well as in Japanese Patent Laid-Open Publication No. 22638/1982.
In these known devices, however, the thumb-retaining member is rotatably supported by its front end portion and has a tongue-shaped lever portion behind the pivot shaft which is pushed downward by the shaft of the thumb to disengage the clutch, as shown in FIG. 14. During this operation the tip of the thumb is raised and separated from the spool flange. Consequently, the thumbing of the spool flange, which must be done concurrently with the clutch manipulation and which requires a smooth and delicate action of the thumb, is often impossible because the fisher is obliged to move his thumb in an unnatural manner. Consequently, problems are often encountered such as the backlash of the fishing line, casting of the lure to a point far from the target, etc. In addition, the user feels fatigue and, at worst, pain in his thumb as a result of repeated operations. These problems are serious, particularly for beginners.
The specification of U.S. Pat. No. 842,551 discloses a construction in which a clutch operation lever is rotatably mounted on one side portion of a support shaft extending between a pair of reel side plates, the clutch operation lever having a free end which extends to a position above the center of the support shaft. In this arrangement, since the operation lever is swung around the axis of a pivot by the pressure of the thumb, it is difficult to effect smooth thumbing by the tip of the thumb on the spool flange. In addition, only the central portion of the area behind the spool is available for manipulation, and the slackened fishing line tends to become entangled with the operation lever, resulting in a abrupt stopping of the release of the fishing line or, in the worst case, the breakage of the fishing line.
In these known arrangements, it is necessary to continue pressing the operation lever during thumbing, because the operation lever is urged upward. This is inconvenient and unsuitable for thumbing which must be done delicately in accordance with the fishing conditions.